• Lassa fever was first discovered in 1969 in the town of Lassa, in Borno State, Nigeria. It was named after the place where the first case occurred. Lassa fever is a member of the Arenaviridae virus family. It was first discovered when two missionary nurses died in Nigeria.
• According to the Centers for Disease Control and Prevention, the number of Lassa virus infections yearly is estimated at 100,000 to 300,000 with approximately 5000 deaths.
• It has an incubation period of 6-21 days. When symptomatic, it starts with fever, general weakness and malaise, then follows with headache, sore throat, muscle and chest pain, vomiting, diarrhea, cough and abdominal pain.
• The virus is shed in the urine droppings of the rats and can be transmitted through direct contact, touching objects and eating food contaminated with these materials or through cuts and sores. Nosocomial transmission occurs in health facilities where infection prevention and control practices are not observed.
• Person to person transmission also occurs most especially when a person comes in contact with the virus in the blood, tissue, secretions or excrement of an infected individual.
• Early symptoms of the disease include fever, headache, chills, diarrhea, nausea, vomiting, sore throat, backache and joint pains.
• 80% of people who become infected with Lassa virus have no symptoms. One in five infections result in severe disease that affects the liver, spleen and kidneys of the infected patients.
• In severe cases, there is facial swelling, fluid in the lung cavity, bleeding from the mouth, nose, vagina, gastrointestinal tract and low blood pressure. Some 25% of patients that survive the disease end up deaf, in about half of these, the hearing returns partially after 3 months. There is some hair loss and gait disturbance that occurs during the recovery period.
• Late symptoms include bleeding from the eyes, ear, nose, bleeding from the mouth and rectum, eye swelling, swelling of the genitals and rashes all over the body that often contains blood.
• The later stages of Lassa fever are shock, seizures, tremor, disorientation and comma. Death occurs within 14 days. For pregnant women, maternal and fetal loss occurs in 80% of cases during the third trimester.
• Early supportive care with rehydration and symptomatic treatment improves the survival rate of the patients of Lassa fever.
PRECAUTIONS AND TREATMENT
• Nigerians have been instructed to stop burning bushes so they don’t drive the rats into close-by houses.
• Lassa can be treated with an antiviral drug called Ribavin. The drug has to administered early.
• Doctors caring for patients with Lassa fever should also monitor fluid, electrolyte and oxygen levels of the patients. There is no vaccine.
• Family members and health care workers are advised to always be careful and avoid contact with blood and body fluids while caring for sick persons with symptoms similar to those listed for Lassa fever and any such patients should be taken to nearest health facility.
LASSA FEVER IN NIGERIA IN THE LAST FIVE YEARS
• The Minister of Health, Prof Isaac Adewole, confirmed that there was an upsurge of Lassa fever in 26 States in 2012.
• In 2005 in Ebonyi State, 5 nurses lost their lives to Lassa fever in the course of duty; 6 cases were reported in the state in 2008 while 2 doctors who died while treating the infected medical personnel. In 2011, there were 7 cases and 2 death. In 2012, there were 20 cases and 6 deaths. In 2013, there were 21 cases and 8 deaths.
• The Federal Ministry of Health said that the number of cases peaked in 2012 when 1, 732 cases were discovered nationwide resulting in 112 fatalities. The disease has been on the decline since 2012.
• In 2012, Lassa fever spread to 12 States in Nigeria and killed 40 people. 397 suspected cases have been recorded in another 12 States: Borno, Gombe, Yobe, Taraba, Plateau, Nasarawa, Edo, Ondo, Rivers, Anambra and Lagos. Only 87 cases have been confirmed.
• Eight doctors and three nurses contracted Lassa fever from a pregnant woman in Ebonyi State in 2014 on whom they performed surgery.
• In 2016, the states affected are Bauchi, Nasarawa, Niger, Taraba, Kano, Ebonyi, Rivers, Edo, Plateau, Gombe and Oyo. Ogun State and Lagos State also have confirmed cases.